Concrete nowadays has an increasingly important role in construction. The volume of monolithic concrete constructions is rising and so is its importance in the design of buildings and infrastructure.
In many cases concrete has become the principal construction material of structures. With the increasing volume and importance of concrete works, the related technology and products are developing rapidly as well. Chemical additives, post-treatment products and adequate reinforcement are very important to achieve a high quality of concrete.
Concrete has a high compressive strength and a relatively low tensile strength. These properties result in reinforcement being used to achieve the required level of structural strength. The most common type of reinforcement is metal. To speed up the on-site work and achieve higher quality, pre-manufactured reinforcement solutions and auxiliary materials are widely used:
- Rebar grids;
- Rebar frames;
- Rebar bends;
- Rebar spacers;
- Tying wire;
- Special tools;
- Ready-made rebar solutions.
Present in the Latvian market for two years, BetonMax Ltd. offers a wide range of products related to the reinforcement of structures and concrete pouring. An important component in the reinforcement of structures (foundations, floors, walls, ceilings) are pre-manufactured reinforcement grids that allow for quick, accurate and efficient preparation of a reinforced plane on site. The reinforcement grids play a special role in industrial objects and high rise construction where the solution of two grids in one plane is used to achieve a "sandwich" required for the foundation, floors, walls and ceilings at high-load locations. This requires double reinforcement. To quickly and efficiently create double reinforcement structures, the metal grid retainers-spacers (MD) are virtually indispensable. They allow two reinforcement grids to be placed parallel to each other and at the required distance from each other during assembly, as well as the pouring of concrete.
BetonMax Ltd. has used its own production facilities to manufacture metal grid retainers-spacers since June 2015. BetonMax Ltd. is the first and so far the only plant in the Baltic states to produce this type of metal grid retainers-spacers (MD) with diagonal reinforcement and physical and mechanical characteristics meeting the highest European standards.
The metal grid retainers-spacers (MD) are placed between vertically or horizontally arranged grids creating walls, floors or ceilings of the required thickness.
The length of the metal grid retainer-spacer (MD) is 2,000 mm, the support area is 200 mm. The recommended distance between parallel metal grid retainers-spacers (MD) is 500 mm. The consumption of metal grid retainers-spacers (MD) is 1 pc. per 1 m2.
The metal grid retainers-spacers (MD) are made from metal wire. S185 steel (according to European classification) is used for production. The parallel wire diameter is 3.8 mm, the diagonal wire diameter is 3.5 mm. The step between the diagonal studs is 200 mm. The available heights are currently from 40 mm to 160 mm. Each of the triangles that form the diagonal is welded to the parallel wire at two points.
Tests and calculations by the Riga Technical University Institute of Mechanics Centre of Expertise of Mechanics have shown that, using a safety coefficient of 1.5, metal grid retainers-spacers (MD) placed according to the manufacturer's recommendations can support a maximum dynamic load of 276 kg/m2 or 2,714 N/m2. The figures stated are confirmed by the Riga Technical University Institute of Mechanics Centre of Expertise of Mechanics expertise statement No. 28.09.15. of 28 September 2015.